1
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Egli L, Work TT. Forest harvest causes rapid changes of maternal investment strategies in ground beetles. Ecology 2024; 105:e4330. [PMID: 38802263 DOI: 10.1002/ecy.4330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 03/05/2024] [Accepted: 04/23/2024] [Indexed: 05/29/2024]
Abstract
Species recovery following anthropogenic disturbances will depend on adaptations in survivorship and fecundity. Life-history theory predicts increased environmental stress will result in (1) shifts in resource allocation from fecundity to body growth/maintenance and (2) increased provisioning among offspring at the cost of reproductive output. For remnant populations that persist after forest harvesting, selection mediated through anthropogenic disturbances may affect resilience to additional stressors such as climate change. We tested how rapid changes in environmental conditions affected maternal investment strategies in two ground beetle species, Pterostichus pensylvanicus and Pterostichus coracinus, by comparing fecundity and survivorship in populations from recently clear-cut and uncut habitats. Using parents drawn from clear-cut or uncut stands, we reared progeny in both common garden and reciprocal transplant experiments. In P. pensylvanicus, we found that neither lineage nor rearing habitat affected the number of eggs laid per female or survivorship of offspring. However, eggs laid by females from clear-cuts were more likely to hatch and offspring reached maturity more quickly, suggesting increased provisioning per offspring. In P. coracinus, females from clear-cuts laid more eggs, and their eggs hatched more rapidly and had greater hatching success, suggesting increased investment in overall reproductive output and increased offspring provisioning. In the reciprocal transplant, we observed significant habitat by lineage interactions on survival in P. coracinus, with survivorship increasing when progeny were reared in novel habitats. In both species, increased maternal investment among offspring was not associated with a reduction in overall reproductive output, as anticipated. However, maternal investment among offspring declined with increasing female size, implying trade-offs between increased metabolic demand and fecundity. Taken together, our work suggests that females from more stressful, clear-cut habitats increased investment in fecundity, compared to females from uncut habitats, and may compensate for larval mortality. These changes were driven by smaller individuals, suggesting that increased environmental stress can influence the relationship between female size and maternal investment strategy. Additionally, reciprocal increases in offspring survivorship in habitats other than the parents suggest that adjacent areas between unharvested and clear-cut habitat may be useful in maintaining biodiversity under future climate stressors.
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Affiliation(s)
- Lauren Egli
- Département des sciences biologiques, Université du Québec à Montréal, Montréal, Québec, Canada
| | - Timothy T Work
- Département des sciences biologiques, Université du Québec à Montréal, Montréal, Québec, Canada
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2
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Iglesias-Carrasco M, Zhang J, Noble DWA. Maternal investment and early thermal conditions affect performance and antipredator responses. Behav Ecol 2024; 35:arae035. [PMID: 38779594 PMCID: PMC11107847 DOI: 10.1093/beheco/arae035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/29/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024] Open
Abstract
Exposure to increased temperatures during early development can lead to phenotypic plasticity in morphology, physiology, and behavior across a range of ectothermic animals. In addition, maternal effects are known to be important contributors to phenotypic variation in offspring. Whether the 2 factors interact to shape offspring morphology and behavior is rarely explored. This is critical because climate change is expected to impact both incubation temperature and maternal stress and resource allocation. Using a fully factorial design, and Bayesian multivariate mixed models, we explored how the manipulation of early thermal environment and yolk-quantity in eggs affected the morphology, performance, and antipredator behavior of 2 sympatric Australian skink species (Lampropholis delicata and L. guichenoti). We found that juveniles from the hot treatment were larger than those on the cold treatment in L. guichenoti but not L. delicata. Using repeated behavioral measures for individual lizards, we found an interaction between incubation temperature and maternal investment in performance, with running speed being affected in a species-specific way by the treatment. We predicted that changes in performance should influence antipredator responses. In support of this prediction, we found that maternal investment impacted antipredator behavior, with animals from the yolk-reduced and cold treatment resuming activity faster after a simulated predatory attack in L. delicata. However, the prediction was not supported in L. guichenoti. Our results highlight the importance of exploring the multifaceted role that environments play across generations to understand how different anthropogenic factors will impact wildlife in the future.
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Affiliation(s)
- Maider Iglesias-Carrasco
- Evolution and Ecology of Sexual Interactions Group, Doñana Biological Station-CSIC, Seville, 41092, Spain
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
| | - Jiayu Zhang
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
| | - Daniel W A Noble
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
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3
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Smaga CR, Bock SL, Johnson JM, Rainwater T, Singh R, Deem V, Letter A, Brunell A, Parrott BB. The influence of incubation temperature on offspring traits varies across northern and southern populations of the American alligator ( Alligator mississippiensis). Ecol Evol 2024; 14:e10915. [PMID: 38371857 PMCID: PMC10869887 DOI: 10.1002/ece3.10915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/10/2024] [Accepted: 01/15/2024] [Indexed: 02/20/2024] Open
Abstract
Maternal provisioning and the developmental environment are fundamental determinants of offspring traits, particularly in oviparous species. However, the extent to which embryonic responses to these factors differ across populations to drive phenotypic variation is not well understood. Here, we examine the contributions of maternal provisioning and incubation temperature to hatchling morphological and metabolic traits across four populations of the American alligator (Alligator mississippiensis), encompassing a large portion of the species' latitudinal range. Our results show that whereas the influence of egg mass is generally consistent across populations, responses to incubation temperature show population-level variation in several traits, including mass, head length, head width, and residual yolk mass. Additionally, the influence of incubation temperature on developmental rate is greater at northern populations, while the allocation of maternal resources toward fat body mass is greater at southern populations. Overall, our results suggest that responses to incubation temperature, relative to maternal provisioning, are a larger source of interpopulation phenotypic variation and may contribute to the local adaptation of populations.
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Affiliation(s)
- Christopher R. Smaga
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
| | - Samantha L. Bock
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
| | - Josiah M. Johnson
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
| | - Thomas Rainwater
- Belle W. Baruch Institute of Coastal Ecology and Forest ScienceClemson UniversityGeorgetownSouth CarolinaUSA
- Tom Yawkey Wildlife CenterGeorgetownSouth CarolinaUSA
| | - Randeep Singh
- Belle W. Baruch Institute of Coastal Ecology and Forest ScienceClemson UniversityGeorgetownSouth CarolinaUSA
| | - Vincent Deem
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation CommissionGainesvilleFloridaUSA
| | - Andrew Letter
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation CommissionGainesvilleFloridaUSA
| | - Arnold Brunell
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation CommissionGainesvilleFloridaUSA
| | - Benjamin B. Parrott
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
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4
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Kar F, Nakagawa S, Noble DWA. Heritability and developmental plasticity of growth in an oviparous lizard. Heredity (Edinb) 2024; 132:67-76. [PMID: 37968348 PMCID: PMC10844306 DOI: 10.1038/s41437-023-00660-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 10/28/2023] [Accepted: 10/29/2023] [Indexed: 11/17/2023] Open
Abstract
Selective processes act on phenotypic variation although the evolutionary potential of a trait relies on the underlying heritable variation. Developmental plasticity is an important source of phenotypic variation, but it can also promote changes in genetic variation, yet we have a limited understanding of how they are both impacted. Here, we quantified the influence of developmental temperature on growth in delicate skinks (Lampropholis delicata) and partitioned total phenotypic variance using an animal model fitted with a genomic relatedness matrix. We measured mass for 261 individuals (nhot = 125, ncold = 136) over 16 months (nobservations = 3002) and estimated heritability and maternal effects over time. Our results show that lizards reared in cold developmental temperatures had consistently higher mass across development compared to lizards that were reared in hot developmental temperatures. However, developmental temperature did not impact the rate of growth. On average, additive genetic variance, maternal effects and heritability were higher in the hot developmental temperature treatment; however, these differences were not statistically significant. Heritability increased with age, whereas maternal effects decreased upon hatching but increased again at a later age, which could be driven by social competition or intrinsic changes in the expression of variation as an individual's growth. Our work suggests that the evolutionary potential of growth is complex, age-dependent and not overtly affected by extremes in natural nest temperatures.
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Affiliation(s)
- Fonti Kar
- School of Biological Earth and Environmental Sciences, Ecology and Evolution Research Centre, University of New South Wales, Sydney, NSW, Australia
| | - Shinichi Nakagawa
- School of Biological Earth and Environmental Sciences, Ecology and Evolution Research Centre, University of New South Wales, Sydney, NSW, Australia
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Daniel W A Noble
- School of Biological Earth and Environmental Sciences, Ecology and Evolution Research Centre, University of New South Wales, Sydney, NSW, Australia.
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
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5
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Ristyadi D, He XZ, Wang Q. Resource allocation strategies for survival and reproduction by an invasive pest in response to intermittent fasting. Curr Zool 2023; 69:600-606. [PMID: 37637313 PMCID: PMC10449421 DOI: 10.1093/cz/zoac068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/24/2022] [Indexed: 08/29/2023] Open
Abstract
Intermittent fasting (IF) is a type of dietary restriction that involves fasting periods in intervals, which has been used as a strategy to improve health and extend longevity. Regular fasting is common during the process of biological invasions in nature. Yet, it is not clear how invasive animals adjust their resource allocations to survival and reproduction when periodical starvation occurs. Here, we used Tetranychus ludeni, a haplodiploid spider mite and an important invasive pest of horticultural crops around the world, to investigate the effects of IF on its life history strategies. We show that IF increased the longevity in females but not in males probably because of differences in resource storage, metabolic rate, and mating cost between sexes. In response to IF, females traded off fecundity and egg size but not the number of daughters for longevity gain, suggesting that T. ludeni females can adjust their life history strategies for population survival and growth during invasion process. Eggs produced by fasted females realized the same hatch rate and resultant young had the same survival rate as those by unfasted ones. In addition, IF had transgenerational maternal effects which prolonged offspring development period. We suggest that the longer immature developmental period can increase the body size of resulting adults, compensating egg size loss for offspring fitness. Our findings provide insight into resource allocations as responses to fasting, knowledge of which can be used for evaluation of pest invasions and for management of animal survival and reproduction by dietary regulations.
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Affiliation(s)
- Dwi Ristyadi
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North, New Zealand
- Agriculture Faculty, Jambi University, Km 15 Mendalo Darat 36361, Jambi, Indonesia
| | - Xiong Z He
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North, New Zealand
| | - Qiao Wang
- School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North, New Zealand
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6
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Johnson JM, Smaga CR, Bock SL, Parrott BB. Maternal provisioning interacts with incubation temperature to affect hatchling mercury exposure in an oviparous reptile. Biol Lett 2023; 19:20230097. [PMID: 37554010 PMCID: PMC10410221 DOI: 10.1098/rsbl.2023.0097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 07/25/2023] [Indexed: 08/10/2023] Open
Abstract
The thermal environment experienced by developing embryos can influence the utilization of maternally provisioned resources. Despite being particularly consequential for oviparous ectotherms, these dynamics are largely unexplored within ecotoxicological frameworks. Here, we test if incubation temperature interacts with maternally transferred mercury to affect subsequent body burdens and tissue distributions of mercury in hatchling American alligators (Alligator mississippiensis). Nine clutches of alligator eggs were collected from a mercury-contaminated reservoir and incubated at either female- or male-promoting temperatures. Total mercury (THg) concentration was measured in egg yolk collected during incubation and in a suite of tissues collected from hatchlings. THg concentrations in residual yolk and blood were higher in hatchlings incubated at cooler, female-promoting temperatures compared to the warmer, male-promoting temperatures. THg concentrations in most tissues were positively correlated with THg concentrations in blood and dermis, and egg yolk THg concentration was the best predictor of THg concentration in many resultant tissues. Our results highlight a hereto unknown role of the developmental environment in mediating tissue specific uptake of contaminants in an oviparous reptile.
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Affiliation(s)
- Josiah M. Johnson
- Savannah River Ecology Laboratory, P.O. Drawer E, Aiken, SC 29802, USA
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Christopher R. Smaga
- Savannah River Ecology Laboratory, P.O. Drawer E, Aiken, SC 29802, USA
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Samantha L. Bock
- Savannah River Ecology Laboratory, P.O. Drawer E, Aiken, SC 29802, USA
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Benjamin B. Parrott
- Savannah River Ecology Laboratory, P.O. Drawer E, Aiken, SC 29802, USA
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
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7
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Marks JR, Sorlin M, Lailvaux SP. The maternal energetic environment affects both egg and offspring phenotypes in green anole lizards ( Anolis carolinensis). Ecol Evol 2023; 13:e9656. [PMID: 36628150 PMCID: PMC9822813 DOI: 10.1002/ece3.9656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 01/08/2023] Open
Abstract
Animals exist in dynamic environments that may affect both their own fitness and that of their offspring. Maternal effects might allow mothers to prepare their offspring for the environment in which they will be born via several mechanisms, not all of which are well understood. Resource scarcity and forced resource allocation are two scenarios that could affect maternal investment by altering the amount and type of resources available for investment in offspring, albeit in potentially different ways. We tested the hypothesis that maternal dietary restriction and sprint training have different consequences for the offspring phenotype in an oviparous lizard (Anolis carolinensis). To do this, we collected and reared eggs from adult diet-manipulated females (low-diet [LD] or high-diet [HD]) and sprint-trained females (sprint trained [ST] or untrained [UT]) and measured both egg characteristics and hatchling morphology. ST and LD mothers laid both the fewest and heaviest eggs, and ST, UT, and LD eggs also had significantly longer incubation periods than the HD group. Hatchlings from the diet experiment (LD and HD offspring) were the heaviest overall. Furthermore, both body mass of the mother at oviposition and change in maternal body mass over the course of the experiment had significant and sometimes different effects on egg and offspring phenotypes, highlighting the importance of maternal energetic state to the allocation of maternal resources.
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Affiliation(s)
- Jamie R. Marks
- Department of BiologyUniversity of New OrleansNew OrleansLouisianaUSA
| | - Mahaut Sorlin
- Department of BiologyUniversity of New OrleansNew OrleansLouisianaUSA
| | - Simon P. Lailvaux
- Department of BiologyUniversity of New OrleansNew OrleansLouisianaUSA
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8
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Sex-specific effects of capital resources on reproductive timing and success in red squirrels. Behav Ecol Sociobiol 2022. [DOI: 10.1007/s00265-022-03245-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Reformulation of Trivers-Willard hypothesis for parental investment. Commun Biol 2022; 5:371. [PMID: 35440689 PMCID: PMC9018816 DOI: 10.1038/s42003-022-03286-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 03/17/2022] [Indexed: 11/08/2022] Open
Abstract
The Trivers-Willard hypothesis (TWH) plays a central role in understanding the optimal investment strategies to male and female offspring. Empirical studies of TWH, however, yielded conflicting results. Here, we present models to predict optimal comprehensive multi-element parental strategies composed of primary sex ratio, brood size, resource allocation among offspring, and the resultant secondary sex ratio. Our results reveal that the optimal strategy depends on sex differences in the shape of offspring fitness function rather than in fitness variance. Also, the slope of the tangent line (through the origin) to the offspring fitness function can be used to predict the preferred offspring sex. We also briefly discuss links between the model and the empirical research. This comprehensive reformulation of TWH will offer a thorough understanding of multi-element parental investment strategies beyond the classical TWH.
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10
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Du WG, Shine R. The behavioural and physiological ecology of embryos: responding to the challenges of life inside an egg. Biol Rev Camb Philos Soc 2022; 97:1272-1286. [PMID: 35166012 DOI: 10.1111/brv.12841] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 02/06/2022] [Accepted: 02/08/2022] [Indexed: 12/24/2022]
Abstract
Adaptations of post-hatching animals have attracted far more study than have embryonic responses to environmental challenges, but recent research suggests that we have underestimated the complexity and flexibility of embryos. We advocate a dynamic view of embryos as organisms capable of responding - on both ecological and evolutionary timescales - to their developmental environments. By viewing embryos in this way, rather than assuming an inability of pre-hatching stages to adapt and respond, we can broaden the ontogenetic breadth of evolutionary and ecological research. Both biotic and abiotic factors affect embryogenesis, and embryos exhibit a broad range of behavioural and physiological responses that enable them to deal with changes in their developmental environments in the course of interactions with their parents, with other embryos, with predators, and with the physical environment. Such plasticity may profoundly affect offspring phenotypes and fitness, and in turn influence the temporal and spatial dynamics of populations and communities. Future research in this field could benefit from an integrated framework that combines multiple approaches (field investigations, manipulative experiments, ecological modelling) to clarify the mechanisms and consequences of embryonic adaptations and plasticity.
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Affiliation(s)
- Wei-Guo Du
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Richard Shine
- Department of Biological Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
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11
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Widowski TM, Cooley L, Hendriksen S, Peixoto MRLV. Maternal age and maternal environment affect egg composition, yolk testosterone, offspring growth and behaviour in laying hens. Sci Rep 2022; 12:1828. [PMID: 35115547 PMCID: PMC8814016 DOI: 10.1038/s41598-022-05491-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 01/04/2022] [Indexed: 11/13/2022] Open
Abstract
Maternal effects have been reported to alter offspring phenotype in laying hens. In this study, we investigated the effects of maternal environment and maternal age on egg traits and offspring development and behaviour. For this, we ran two experiments. First (E1), commercial hybrid hens were reared either in aviary or barren brooding cages, then housed in aviary, conventional cages or furnished (enriched) cages, thus forming different maternal housing treatments. Hens from each treatment were inseminated at three ages, and measures of egg composition, yolk testosterone concentration and offspring’s development, anxiety and fearfulness were assessed. In experiment 2 (E2), maternal age effects on offspring's growth and behaviour were further investigated using fertile eggs from commercial breeder flocks at three different ages. Results from E1 showed that Old hens laid heavier eggs with less yolk testosterone and produced offspring with fewer indicators of anxiety and fearfulness. Maternal rearing and housing affected egg traits, offspring weight and behaviour, but not in a consistent way. Effects of maternal age were not replicated in E2, possibly due to differences in management or higher tolerance to maternal effects in commercial breeders. Overall, our research confirms that maternal age and maternal environment affects egg composition, with maternal age specifically affecting yolk testosterone concentration, which may mediate physical and behavioural effects in offspring.
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Affiliation(s)
- Tina M Widowski
- Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
| | | | - Simone Hendriksen
- Department of Animal Sciences, Behavioural Ecology Group, Wageningen University, PO Box 338, 6700 AH, Wageningen, The Netherlands
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12
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Josimovich JM, Falk BG, Grajal-Puche A, Hanslowe EB, Bartoszek IA, Reed RN, Currylow AF. Clutch may predict growth of hatchling Burmese pythons better than food availability or sex. Biol Open 2021; 10:273482. [PMID: 34796905 PMCID: PMC8609237 DOI: 10.1242/bio.058739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 10/21/2021] [Indexed: 12/20/2022] Open
Abstract
Identifying which environmental and genetic factors affect growth pattern phenotypes can help biologists predict how organisms distribute finite energy resources in response to varying environmental conditions and physiological states. This information may be useful for monitoring and managing populations of cryptic, endangered, and invasive species. Consequently, we assessed the effects of food availability, clutch, and sex on the growth of invasive Burmese pythons (Python bivittatus Kuhl) from the Greater Everglades Ecosystem in Florida, USA. Though little is known from the wild, Burmese pythons have been physiological model organisms for decades, with most experimental research sourcing individuals from the pet trade. Here, we used 60 hatchlings collected as eggs from the nests of two wild pythons, assigned them to High or Low feeding treatments, and monitored growth and meal consumption for 12 weeks, a period when pythons are thought to grow very rapidly. None of the 30 hatchlings that were offered food prior to their fourth week post-hatching consumed it, presumably because they were relying on internal yolk stores. Although only two clutches were used in the experiment, we found that nearly all phenotypic variation was explained by clutch rather than feeding treatment or sex. Hatchlings from clutch 1 (C1) grew faster and were longer, heavier, in better body condition, ate more frequently, and were bolder than hatchlings from clutch 2 (C2), regardless of food availability. On average, C1 and C2 hatchling snout-vent length (SVL) and weight grew 0.15 cm d−1 and 0.10 cm d−1, and 0.20 g d−1 and 0.03 g d−1, respectively. Additional research may be warranted to determine whether these effects remain with larger clutch sample sizes and to identify the underlying mechanisms and fitness implications of this variation to help inform risk assessments and management. This article has an associated First Person interview with the first author of the paper. Summary: Hatchling pythons from an invasive population displayed substantial phenotypic variation in morphometrics, growth rates, and behaviors. This information may be useful for managing populations of cryptic, endangered, and invasive species.
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Affiliation(s)
- Jillian M Josimovich
- U.S. Geological Survey, Fort Collins Science Center - South Florida Field Station, 40001 SR 9336, Homestead, FL 33034, USA
| | - Bryan G Falk
- U.S. Geological Survey, Fort Collins Science Center - South Florida Field Station, 40001 SR 9336, Homestead, FL 33034, USA
| | - Alejandro Grajal-Puche
- U.S. Geological Survey, Fort Collins Science Center - South Florida Field Station, 40001 SR 9336, Homestead, FL 33034, USA
| | - Emma B Hanslowe
- U.S. Geological Survey, Fort Collins Science Center - South Florida Field Station, 40001 SR 9336, Homestead, FL 33034, USA
| | | | - Robert N Reed
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO 80526, USA
| | - Andrea F Currylow
- U.S. Geological Survey, Fort Collins Science Center - South Florida Field Station, 40001 SR 9336, Homestead, FL 33034, USA
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13
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Pruett JE, Warner DA. Spatial and temporal variation in phenotypes and fitness in response to developmental thermal environments. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13910] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Jenna E. Pruett
- Department of Biological Sciences Auburn University Auburn Alabama USA
| | - Daniel A. Warner
- Department of Biological Sciences Auburn University Auburn Alabama USA
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14
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Beatty AE, Mote DM, Schwartz TS. Tails of reproduction: Regeneration leads to increased reproductive investment. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:522-528. [PMID: 33970527 DOI: 10.1002/jez.2472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/29/2021] [Accepted: 04/26/2021] [Indexed: 11/11/2022]
Abstract
Trade-offs between life-history traits are due to limited resources or constraints in the regulation of genetic and physiological networks. Tail autotomy, with subsequent regeneration, is a common anti-predation mechanism in lizards and is predicted to trade-off with life-history traits, such as reproduction. We utilize the brown anole lizard with its unusual reproductive pattern of single-egg clutches every 7-10 days to test for a trade-off in reproductive investment over 8 weeks of tail regeneration on a limited diet. In contrast to predictions, we found that investing in tissue regeneration had a positive effect on reproduction in terms of egg size (11.7% relative to controls) and hatchling size (11.5% relative to controls), and no effect on egg number or survival, with the increase in reproduction starting at peak regeneration. We discuss mechanistic hypotheses that the process of regeneration may cause increased energetic efficiency or utilized shared physiological pathways with reproductive investment.
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Affiliation(s)
- Abby E Beatty
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - David M Mote
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Tonia S Schwartz
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
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15
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Gatto CR, Matthews B, Reina RD. Role of incubation environment in determining thermal tolerance of sea turtle hatchlings. ENDANGER SPECIES RES 2021. [DOI: 10.3354/esr01111] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Warming global temperatures are predicted to reduce population viability in many oviparous ectothermic taxa, with increased embryonic mortality likely to be a main cause. While research on embryonic upper thermal limits is extensive, sea turtle hatchling thermal tolerance has received less attention and our understanding of how incubation conditions influence hatchling thermal tolerance is limited. Here, we report green turtle Chelonia mydas hatchling hydration and thermal tolerance following incubation in dry and wet conditions. We used packed cell volume and total protein as indicators of hydration and measured the critical thermal maximum (CTmax) of hatchlings in air. Neither hydration nor thermal tolerance was directly influenced by moisture treatment. However, hatchlings from moister nests had longer incubation durations (wet: 60.11 d vs. dry: 54.86 d), and, using incubation duration as a proxy for incubation temperature, hatchlings from cooler nests had significantly lower CTmax (wet: 39.84°C vs. dry: 40.51°C). Thus, despite not directly influencing thermal tolerance, moisture treatment influenced nest temperature indirectly; hatchlings that experienced warmer conditions in dry nests had a higher thermal tolerance than hatchlings from cooler and wetter nests. Ectothermic neonates may have greater plasticity in their thermal tolerance than previously thought, but their ability to adapt to increasing temperature is likely limited. Additionally, common management techniques to reduce nest temperatures, such as watering and shading nests, may only reduce embryonic mortality at the cost of decreased hatchling thermal tolerance and increased hatchling mortality during emergence. Nesting-site management interventions designed to reduce embryonic mortality will need to consider mitigation of the possible effects of those interventions on hatchling mortality.
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Affiliation(s)
- CR Gatto
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - B Matthews
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - RD Reina
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
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16
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Liu G, Cain K, Schwanz L. Maternal Temperature, Corticosterone, and Body Condition as Mediators of Maternal Effects in Jacky Dragons ( Amphibolurus muricatus). Physiol Biochem Zool 2021; 93:434-449. [PMID: 33104412 DOI: 10.1086/711955] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractTemperature is a crucial environmental component that imposes physiological constraints and ultimately produces variation in life-history traits. Temperatures experienced by mothers can influence offspring phenotypes, including growth and sex ratios, especially in ectothermic species. However, mechanisms by which thermal information can be passed onto offspring have been underexplored. Here, we investigated corticosterone as a potential mediator of thermal maternal effects. We held female jacky dragons (Amphibolurus muricatus) in two different thermal regimes (short [7 h] or long [11 h] basking treatments), then quantified plasma corticosterone levels and tested for correlations between the resulting corticosterone levels and reproductive outputs. Lizards in the long-bask treatment had significantly higher corticosterone levels than those in the short-bask treatment. Maternal corticosterone, in turn, had sex-dependent effects on offspring hatching size but was not associated with maternal reproductive effort or offspring sex or growth. In contrast, maternal body condition was strongly positively related to both reproductive output (including clutch size and total number of eggs) and offspring size at hatching but had no effect on offspring growth. Basking treatment also interacted with condition and corticosterone to affect egg mass and hatchling snout-vent length, respectively. When we tested for relationships between corticosterone levels and body condition, we found corticosterone to be negatively related to condition in long-bask lizards but only in the postbreeding season. These findings indicate that thermal opportunity alters physiology, with potential consequences for fitness. Moreover, the results suggest interactive influences of temperature, corticosterone, and condition as mediators of maternal effects.
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17
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Baxter-Gilbert J, Riley JL, Frère CH, Whiting MJ. Shrinking into the big city: influence of genetic and environmental factors on urban dragon lizard morphology and performance capacity. Urban Ecosyst 2020. [DOI: 10.1007/s11252-020-01065-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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18
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Murphy KM, Radder RS, Shine R, Warner DA. Lizard Embryos Prioritize Posthatching Energy Reserves over Increased Hatchling Body Size during Development. Physiol Biochem Zool 2020; 93:339-346. [PMID: 32692615 DOI: 10.1086/710053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Embryonic development in oviparous organisms is fueled by maternally allocated yolk, and many organisms hatch before that energy store is used completely; the resultant leftover (residual) yolk is internalized and may support early posthatching life. However, embryos that use most, or all, of their yolk supply before hatching should hatch at a larger size than those that do not exhaust those energy reserves, which could also have benefits for posthatching growth and survival. To examine the trade-off between residual yolk and offspring size, we experimentally reduced yolk quantity at oviposition in lizard eggs (Amphibolurus muricatus) and then quantified offspring size and the amount of internalized residual yolk. This design enabled us to determine whether embryos (1) exhaust yolk supply during development (thereby maximizing neonatal size) or (2) reduce neonatal size by retaining yolk reserves at hatching. Our data support the latter scenario. Eggs from the yolk-reduced treatment produced smaller offspring with a proportion of residual yolk similar to that of offspring from unmanipulated eggs, suggesting that the fitness benefits of posthatching energy stores outweigh those of larger neonatal size.
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19
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Vanden Broecke B, Bongers A, Mnyone L, Matthysen E, Leirs H. Nonlinear maternal effects on personality in a rodent species with fluctuating densities. Curr Zool 2020; 67:1-9. [PMID: 33654484 PMCID: PMC7901759 DOI: 10.1093/cz/zoaa032] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 06/16/2020] [Indexed: 02/06/2023] Open
Abstract
Consistent among-individual variation in behavior, or animal personality, is present in a wide variety of species. This behavioral variation is maintained by both genetic and environmental factors. Parental effects are a special case of environmental variation and are expected to evolve in populations experiencing large fluctuations in their environment. They represent a non-genetic pathway by which parents can transmit information to their offspring, by modulating their personality. While it is expected that parental effects contribute to the observed personality variation, this has rarely been studied in wild populations. We used the multimammate mouse Mastomys natalensis as a model system to investigate the potential effects of maternal personality on offspring behavior. We did this by repeatedly recording the behavior of individually housed juveniles which were born and raised in the lab from wild caught females. A linear correlation, between mother and offspring in behavior, would be expected when the personality is only affected by additive genetic variation, while a more complex relationship would suggests the presence of maternal effects. We found that the personality of the mother predicted the behavior of their offspring in a non-linear pattern. Exploration behavior of mother and offspring was positively correlated, but only for slow and average exploring mothers, while this correlation became negative for fast exploring mothers. This may suggests that early maternal effects could affect personality in juvenile M. natalensis, potentially due to density-dependent and negative frequency-dependent mechanisms, and therefore contribute to the maintenance of personality variation.
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Affiliation(s)
- Bram Vanden Broecke
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Aurelia Bongers
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Ladslaus Mnyone
- Pest Management Centre, Sokoine University of Agriculture, P.O.Box 3110 Chuo Kikuu, Morogoro, Tanzania
| | - Erik Matthysen
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Herwig Leirs
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Antwerp, Belgium
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20
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Steele AL, Warner DA. Sex-specific effects of developmental temperature on morphology, growth and survival of offspring in a lizard with temperature-dependent sex determination. Biol J Linn Soc Lond 2020. [DOI: 10.1093/biolinnean/blaa038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThe developmental environment plays a pivotal role in shaping fitness-relevant phenotypes of all organisms. Phenotypes are highly labile during embryogenesis, and environmental factors experienced early in development can have profound effects on fitness-relevant traits throughout life. Many reptiles exhibit temperature-dependent sex determination (TSD), whereby temperature during embryonic development permanently determines offspring sex. The leading hypothesis for the adaptive significance of TSD posits that egg incubation temperature differentially affects the fitness of males vs. females so that each sex is produced at its optimal temperature. The goal of this research is to address this hypothesis by quantifying the sex-specific effects of incubation temperature on phenotypes and survival in a lizard (Agama picticauda) with TSD. By incubating eggs under constant and fluctuating temperatures, we demonstrated that incubation temperature affects fitness-relevant phenotypes in A. picticauda; but males and females had similar reaction norms. However, females produced from female-biased incubation temperatures had greater survival than those from male-biased temperatures, and male survival was lowest for individuals produced from a female-biased temperature. In addition, eggs incubated at male-biased temperatures hatched earlier than those incubated at female-biased temperatures, which may have sex-specific consequences later in life as predicted by models for the adaptive significance of TSD.
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Affiliation(s)
- Ariel L Steele
- Department of Biological Sciences, Auburn University, Auburn, AL, USA
| | - Daniel A Warner
- Department of Biological Sciences, Auburn University, Auburn, AL, USA
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21
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Hall JM, Mitchell TS, Thawley CJ, Stroud JT, Warner DA. Adaptive seasonal shift towards investment in fewer, larger offspring: Evidence from field and laboratory studies. J Anim Ecol 2020; 89:1242-1253. [DOI: 10.1111/1365-2656.13182] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 01/09/2020] [Indexed: 11/27/2022]
Affiliation(s)
- Joshua M. Hall
- Department of Biological Sciences Auburn University Auburn AL USA
| | - Timothy S. Mitchell
- Department of Biological Sciences Auburn University Auburn AL USA
- Department of Ecology, Evolution and Behavior University of Minnesota St. Paul MN USA
| | - Christopher J. Thawley
- Department of Biological Sciences University of Rhode Island Kingston RI USA
- Department of Biology Davidson College Davidson NC USA
| | - James T. Stroud
- Department of Biology Washington University St. Louis MO USA
| | - Daniel A. Warner
- Department of Biological Sciences Auburn University Auburn AL USA
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22
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Tiatragul S, Hall JM, Warner DA. Nestled in the city heat: urban nesting behavior enhances embryo development of an invasive lizard. JOURNAL OF URBAN ECOLOGY 2020. [DOI: 10.1093/jue/juaa001] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Abstract
Urbanization transforms many aspects of natural landscapes and poses many new challenges for individual survival and population persistence. Thus, urbanization provides an opportunity to examine how organisms deal with novel environmental change. Many studies provide evidence of phenotypic adaptation to urban environments, but few focus on responses during early life stages. Filling this information gap is important, because early life stages are particularly sensitive to abiotic factors, and no population is sustainable without successful embryo development. We tested the hypotheses that (i) embryos tolerate warmer temperature conditions of urbanized areas and (ii) maternal nesting behavior protects embryos from potentially lethal thermal conditions in urbanized habitats. We studied introduced populations of a subtropical lizard, Anolis cristatellus, in suburban and forested areas in Miami, Florida. In each habitat, we measured microenvironment variables for locations that females used for nesting vs. locations they did not use. We then incubated eggs from both populations under thermal conditions that mimicked used and unused sites. Nests in the suburban site were warmer than in the forest; however, in the suburban site, locations that females used were relatively cool compared with locations that were not used. We found no evidence that embryos are adapted to their respective suburban or forested thermal environments, but rather maternal nest-site choice enhanced embryo development in the suburban habitat. Maternal nesting behavior is likely an important factor for population persistence under major environmental changes, and a key contributor to the establishment and spread of invasive organisms across urbanized landscapes.
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Affiliation(s)
- Sarin Tiatragul
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Joshua M Hall
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Daniel A Warner
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
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23
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Hanover AM, Husak JF, Lovern M. Corticosterone in Lizard Egg Yolk Is Reduced by Maternal Diet Restriction but Unaltered by Maternal Exercise. Physiol Biochem Zool 2019; 92:573-578. [PMID: 31584858 DOI: 10.1086/705708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
When females face adverse environmental conditions, physiological changes, such as elevated corticosterone levels, to cope with the stressors may also impact their offspring. Such maternal effects are often considered adaptive and may "prime" the offspring for the same adverse environment, but maternal corticosterone levels do not always match that of the eggs produced. We examined how diet restriction and increased locomotor activity, via exercise training, affected steroid hormone levels of female green anole lizards, as well as the hormone levels in the yolk of their eggs. Diet restriction did not affect female hormone levels, but training increased corticosterone levels. Despite this, training did not affect yolk steroid levels, but eggs from females with diet restriction had lower corticosterone levels in yolk. This suggests that two common stressors, food shortage and increased locomotor activity, impact female physiology in a way that is not translated to her offspring.
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24
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Zipple MN, Archie EA, Tung J, Altmann J, Alberts SC. Intergenerational effects of early adversity on survival in wild baboons. eLife 2019; 8:e47433. [PMID: 31549964 PMCID: PMC6759315 DOI: 10.7554/elife.47433] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 08/06/2019] [Indexed: 01/09/2023] Open
Abstract
Early life adversity can affect an individual's health, survival, and fertility for many years after the adverse experience. Whether early life adversity also imposes intergenerational effects on the exposed individual's offspring is not well understood. We fill this gap by leveraging prospective, longitudinal data on a wild, long-lived primate. We find that juveniles whose mothers experienced early life adversity exhibit high mortality before age 4, independent of the juvenile's own experience of early adversity. These juveniles often preceded their mothers in death by 1 to 2 years, indicating that high adversity females decline in their ability to raise offspring near the end of life. While we cannot exclude direct effects of a parent's environment on offspring quality (e.g., inherited epigenetic changes), our results are completely consistent with a classic parental effect, in which the environment experienced by a parent affects its future phenotype and therefore its offspring's phenotype.
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Affiliation(s)
| | - Elizabeth A Archie
- Department of Biological SciencesUniversity of Notre DameSouth BendUnited States
- Institute of Primate Research, National Museums of KenyaNairobiKenya
| | - Jenny Tung
- Department of BiologyDuke UniversityDurhamUnited States
- Institute of Primate Research, National Museums of KenyaNairobiKenya
- Department of Evolutionary AnthropologyDuke UniversityDurhamUnited States
- Duke Population Research InstituteDuke UniversityDurhamUnited States
| | - Jeanne Altmann
- Institute of Primate Research, National Museums of KenyaNairobiKenya
- Department of Ecology and Evolutionary BiologyPrinceton UniversityPrincetonUnited States
| | - Susan C Alberts
- Department of BiologyDuke UniversityDurhamUnited States
- Institute of Primate Research, National Museums of KenyaNairobiKenya
- Department of Evolutionary AnthropologyDuke UniversityDurhamUnited States
- Duke Population Research InstituteDuke UniversityDurhamUnited States
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25
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Pearson PR, Warner DA. Early hatching enhances survival despite beneficial phenotypic effects of late-season developmental environments. Proc Biol Sci 2019. [PMID: 29540523 DOI: 10.1098/rspb.2018.0256] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Seasonal shifts in environmental conditions provide predictable cues to which organisms can respond in adaptive ways. For example, seasonal changes in temperature can induce phenotypes at different times of the year that have season-specific fitness benefits. Here, we tested the hypothesis that embryo responses to seasonal changes in thermal environments are adaptively matched to the timing of reproduction (environmental-matching hypothesis). We collected eggs of the brown anole lizard (Anolis sagrei) from early and late seasons, and exposed them to early and late thermal regimes that mimic nest temperatures. After measuring offspring morphology and performance, we quantified their survival in the field. Females had higher fecundity, but produced smaller eggs, early in the season compared with late in the season. Late-season eggs exposed to late thermal regimes had relatively high survival, but early-season eggs exposed to early thermal regimes had similar survival rates to those exposed to mismatched conditions. Late-season nest temperatures and late-season eggs produced offspring that were relatively large and fast runners. However, despite phenotypic benefits of late-season conditions, early-season hatchlings had greater survival in the field. Our results do not fully support the environmental-matching hypothesis but suggest that selection favours seasonal shifts in reproductive investment of mothers (high early-season fecundity) over plastic responses of embryos to seasonal environmental changes.
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Affiliation(s)
- P R Pearson
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA .,Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - D A Warner
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA.,Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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26
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Kouyoumdjian L, Gangloff EJ, Souchet J, Cordero GA, Dupoué A, Aubret F. Transplanting gravid lizards to high elevation alters maternal and embryonic oxygen physiology, but not reproductive success or hatchling phenotype. J Exp Biol 2019; 222:jeb.206839. [DOI: 10.1242/jeb.206839] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 06/19/2019] [Indexed: 12/13/2022]
Abstract
Increased global temperatures have opened previously inhospitable habitats, such as at higher elevations. However, the reduction of oxygen partial pressure with increase in elevation represents an important physiological constraint that may limit colonization of such habitats, even if the thermal niche is appropriate. To test the mechanisms underlying the response to ecologically-relevant levels of hypoxia, we performed a translocation experiment with the common wall lizard (Podarcis muralis), a widespread European lizard amenable to establishing populations outside its natural range. We investigated the impacts of hypoxia on the oxygen physiology and reproductive output of gravid common wall lizards and the subsequent development and morphology of their offspring. Lowland females transplanted to high elevations increased their haematocrit and haemoglobin concentration within days and maintained routine metabolism compared to lizards kept at native elevations. However, transplanted lizards suffered from increased reactive oxygen metabolite production near the oviposition date, suggesting a cost of reproduction at high elevation. Transplanted females and females native to different elevations did not differ in reproductive output (clutch size, egg mass, relative clutch mass, or embryonic stage at oviposition) or in post-oviposition body condition. Developing embryos reduced heart rates and prolonged incubation times at high elevations within the native range and at extreme high elevations beyond the current range, but this reduced oxygen availability did not affect metabolic rate, hatching success, or hatchling size. These results suggest that this opportunistic colonizer is capable of successfully responding to novel environmental constraints in these important life-history stages.
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Affiliation(s)
- Laura Kouyoumdjian
- Station d'Ecologie Théorique et Expérimentale du CNRS – UMR 5321, Moulis, France
| | - Eric J. Gangloff
- Station d'Ecologie Théorique et Expérimentale du CNRS – UMR 5321, Moulis, France
| | - Jérémie Souchet
- Station d'Ecologie Théorique et Expérimentale du CNRS – UMR 5321, Moulis, France
| | - Gerardo A. Cordero
- Fachbereich Geowissenschaften, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Andréaz Dupoué
- CNRS UPMC, UMR 7618, iEES Paris, Université Pierre et Marie Curie, Paris, France
| | - Fabien Aubret
- Station d'Ecologie Théorique et Expérimentale du CNRS – UMR 5321, Moulis, France
- School of Molecular and Life Sciences, Curtin University, 6102 WA, Australia
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27
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Hall JM, Buckelew A, Lovern M, Secor SM, Warner DA. Seasonal Shifts in Reproduction Depend on Prey Availability for an Income Breeder. Physiol Biochem Zool 2018; 91:1129-1147. [DOI: 10.1086/700341] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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28
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Hall JM, Warner DA. Thermal spikes from the urban heat island increase mortality and alter physiology of lizard embryos. J Exp Biol 2018; 221:221/14/jeb181552. [DOI: 10.1242/jeb.181552] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/15/2018] [Indexed: 01/04/2023]
Abstract
ABSTRACT
Effects of global change (i.e. urbanization, climate change) on adult organisms are readily used to predict the persistence of populations. However, effects on embryo survival and patterns of development are less studied, even though embryos are particularly sensitive to abiotic conditions that are altered by global change (e.g. temperature). In reptiles, relatively warm incubation temperatures increase developmental rate and often enhance fitness-relevant phenotypes, but extremely high temperatures cause death. Due to the urban heat island effect, human-altered habitats (i.e. cities) potentially create unusually warm nest conditions that differ from adjacent natural areas in both mean and extreme temperatures. Such variation may exert selection pressures on embryos. To address this, we measured soil temperatures in places where the Puerto Rican crested anole lizard (Anolis cristatellus) nests in both city and forest habitats. We bred anoles in the laboratory and subjected their eggs to five incubation treatments that mimicked temperature regimes from the field, three of which included brief exposure to extremely high temperatures (i.e. thermal spikes) measured in the city. We monitored growth and survival of hatchlings in the laboratory for 3 months and found that warmer, city temperatures increase developmental rate, but brief, thermal spikes reduce survival. Hatchling growth and survival were unaffected by incubation treatment. The urban landscape can potentially create selection pressures that influence organisms at early (e.g. embryo) and late life stages. Thus, research aimed at quantifying the impacts of urbanization on wildlife populations must include multiple life stages to gain a comprehensive understanding of this important aspect of global change.
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Affiliation(s)
- Joshua M. Hall
- Auburn University, Department of Biological Sciences, 101 Rouse Life Sciences Building, Auburn, AL 36849, USA
| | - Daniel A. Warner
- Auburn University, Department of Biological Sciences, 101 Rouse Life Sciences Building, Auburn, AL 36849, USA
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29
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Van Dyke JU, Griffith OW. Mechanisms of reproductive allocation as drivers of developmental plasticity in reptiles. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:275-286. [PMID: 29733527 DOI: 10.1002/jez.2165] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/09/2018] [Accepted: 04/13/2018] [Indexed: 12/30/2022]
Abstract
Developmental plasticity in offspring phenotype occurs as a result of the environmental conditions embryos experience during development. The nutritional environment provided to a fetus is an important source of developmental plasticity. Reptiles are a particularly interesting system to study this plasticity because of their varied routes of maternal nutrient allocation to reproduction. Most reptiles provide their offspring with all or most of the nutrients they require in egg yolk (lecithotrophy) while viviparous reptiles also provide their offspring with nutrients via a placenta (placentotrophy). We review the ways in which both lecithotrophy and placentotrophy can lead to differences in the nutrients embryonic reptiles receive, and discuss how these differences lead to developmental plasticity in offspring phenotype. We finish by reviewing the ecological and conservation consequences of nutritional-driven developmental plasticity in reptiles. If nutritional-driven developmental plasticity has fitness consequences, then understanding the basis of this plasticity has exciting potential to identify how reptile recruitment is affected by environmental changes in food supply. Such knowledge is critical to our ability to protect taxa threatened by environmental change.
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Affiliation(s)
- James U Van Dyke
- School of Environmental Sciences, Institute of Land, Water & Society, Charles Sturt University, Albury, NSW, Australia
| | - Oliver W Griffith
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut.,Yale Systems Biology Institute, Yale University, West Haven, Connecticut
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30
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Andrews RM. Developmental plasticity in reptiles: Insights into thermal and maternal effects on chameleon phenotypes. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:298-307. [DOI: 10.1002/jez.2160] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/16/2018] [Accepted: 03/24/2018] [Indexed: 02/03/2023]
Affiliation(s)
- Robin M. Andrews
- Department of Biological Sciences; Virginia Tech; Blacksburg Virginia
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31
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Mitchell TS, Hall JM, Warner DA. Female investment in offspring size and number shifts seasonally in a lizard with single-egg clutches. Evol Ecol 2018. [DOI: 10.1007/s10682-018-9936-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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32
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González-Medina E, Castillo-Guerrero JA, Herzka SZ, Fernández G. High quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird. PLoS One 2018; 13:e0193136. [PMID: 29462199 PMCID: PMC5819808 DOI: 10.1371/journal.pone.0193136] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 02/05/2018] [Indexed: 11/19/2022] Open
Abstract
Understanding the role of diet in the physiological condition of adults during reproduction and hence its effect on reproductive performance is fundamental to understand reproductive strategies in long-lived animals. In birds, little is known about the influence of the quality of food consumed at the beginning of the reproductive period and its short-term effects on reproductive performance. To assess the role of diet in the physiological condition of female blue-footed booby, Sula nebouxii (BFBO), during reproduction we evaluated whether individual differences in diet (assessed by using δ13C and δ15N values of whole blood from female birds and muscle tissue of the principal prey species) prior to egg laying and during incubation influenced their lipid metabolic profile (measured as triglyceride levels and C:N ratio) and their reproductive performance (defined by laying date, clutch size and hatching success). Females with higher δ15N values in their blood during the courtship and incubation periods had a higher lipid metabolic profile, earlier laying date, greater clutch size (2-3 eggs) and higher hatching success. Females that laid earlier and more eggs (2-3 eggs) consumed more Pacific anchoveta (Cetengraulis mysticetus) and Pacific thread herring (Opisthonema libertate) than did other females. These two prey species also had high amounts of lipids (C:N ratio) and caloric content (Kcal/g fresh weight). The quality of food consumed by females at the beginning of reproduction affected their physiological condition, as well as their short-term reproductive performance. Our work emphasizes the importance of determining the influence of food quality during reproduction to understand the reproductive decisions and consequences in long-lived animals.
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Affiliation(s)
- Erick González-Medina
- Posgrado de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Ciudad Universitaria, México D.F., Mexico
- * E-mail: (GF); (EGM)
| | - José Alfredo Castillo-Guerrero
- CONACYT- –Universidad de Guadalajara, Departamento de Estudios para el Desarrollo Sustentable de la Zona Costera, Centro Universitario de la Costa Sur, San Patricio– Melaque, Municipio de Cihuatlán, Jalisco, Mexico
| | - Sharon Zinah Herzka
- Departamento de Oceanografía Biológica, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Baja California, Mexico
| | - Guillermo Fernández
- Unidad Académica Mazatlán, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Mazatlán, Mexico
- * E-mail: (GF); (EGM)
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33
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Pearson PR, Warner DA. Habitat- and season-specific temperatures affect phenotypic development of hatchling lizards. Biol Lett 2017; 12:rsbl.2016.0646. [PMID: 28120809 DOI: 10.1098/rsbl.2016.0646] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 09/30/2016] [Indexed: 11/12/2022] Open
Abstract
Embryonic environments influence phenotypic development, but relatively few experiments have explored the effects of natural environmental variation. We incubated eggs of the lizard Anolis sagrei under conditions that mimicked natural spatial and temporal thermal variation to determine their effects on offspring morphology and performance. Incubation temperatures mimicked two microhabitats (open, shade) at two different times of the incubation season (April, July). Egg survival, incubation duration and offspring size were influenced by interactions between habitat- and season-specific nest temperatures, and locomotor performance was influenced primarily by temporal factors. These findings highlight the importance of spatial and temporal environmental variation in generating variation in fitness-related phenotypes.
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Affiliation(s)
- P R Pearson
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA .,Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - D A Warner
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.,Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
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34
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Gangloff EJ, Sparkman AM, Bronikowski AM. Among-individual heterogeneity in maternal behaviour and physiology affects reproductive allocation and offspring life-history traits in the garter snakeThamnophis elegans. OIKOS 2017. [DOI: 10.1111/oik.04204] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Eric J. Gangloff
- Dept. of Ecology; Evolution and Organismal Biology, Iowa State Univ.; Ames IA USA
- Station d'Ecologie Théorique et Expérimentale du CNRS; FR-09200 Moulis France
| | | | - Anne M. Bronikowski
- Dept. of Ecology; Evolution and Organismal Biology, Iowa State Univ.; Ames IA USA
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35
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Duryea MC, Bergeron P, Clare-Salzler Z, Calsbeek R. Field estimates of parentage reveal sexually antagonistic selection on body size in a population of Anolis lizards. Ecol Evol 2017; 6:7024-7031. [PMID: 28725379 PMCID: PMC5513217 DOI: 10.1002/ece3.2443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/01/2016] [Accepted: 08/04/2016] [Indexed: 11/15/2022] Open
Abstract
Sexual dimorphism evolves when selection favors different phenotypic optima between the sexes. Such sexually antagonistic selection creates intralocus sexual conflict when traits are genetically correlated between the sexes and have sex‐specific optima. Brown anoles are highly sexually dimorphic: Males are on average 30% longer than females and 150% heavier in our study population. Viability selection on body size is known to be sexually antagonistic, and directional selection favors large male size whereas stabilizing selection constrains females to remain small. We build on previous studies of viability selection by measuring sexually antagonistic selection using reproductive components of fitness over three generations in a natural population of brown anoles. We estimated the number of offspring produced by an individual that survived to sexual maturity (termed RSV), a measure of individual fitness that includes aspects of both individual reproductive success and offspring survival. We found directional selection on male body size, consistent with previous studies of viability selection. However, selection on female body size varied among years, and included periods of positive directional selection, quadratic stabilizing selection, and no selection. Selection acts differently in the sexes based on both survival and reproduction and sexual conflict appears to be a persistent force in this species.
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Affiliation(s)
- Mary C Duryea
- Department of Biological Sciences Dartmouth College Hanover NH USA.,Present address: Department of Biology Lund University Lund Sweden
| | - Patrick Bergeron
- Department of Biological Sciences Dartmouth College Hanover NH USA.,Present address: Department of Biological Sciences Bishop's University Sherbrooke QC Canada
| | - Zachary Clare-Salzler
- Department of Biological Sciences Dartmouth College Hanover NH USA.,Present address: Division of Biological Sciences University of Montana Missoula MT USA
| | - Ryan Calsbeek
- Department of Biological Sciences Dartmouth College Hanover NH USA
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36
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Vrtílek M, Polačik M, Reichard M. The role of energetic reserves during embryonic development of an annual killifish. Dev Dyn 2017; 246:838-847. [DOI: 10.1002/dvdy.24528] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 05/04/2017] [Accepted: 05/25/2017] [Indexed: 01/20/2023] Open
Affiliation(s)
- Milan Vrtílek
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic; Brno Czech Republic
| | - Matej Polačik
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic; Brno Czech Republic
| | - Martin Reichard
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic; Brno Czech Republic
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37
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Wang Y, Li S, Zeng Z, Liang L, Du W. Maternal food availability affects offspring performance and survival in a viviparous lizard. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12903] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Yang Wang
- Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing100101 China
- University of Chinese Academy of Science Beijing China
| | - Shu‐Ran Li
- Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing100101 China
- University of Chinese Academy of Science Beijing China
| | - Zhi‐Gao Zeng
- Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing100101 China
| | - Liang Liang
- Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing100101 China
- University of Chinese Academy of Science Beijing China
| | - Wei‐Guo Du
- Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing100101 China
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38
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Embryonic yolk removal affects neither morphology nor escape performance of larval axolotls. ZOOLOGY 2017; 122:7-15. [PMID: 28365231 DOI: 10.1016/j.zool.2017.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 01/02/2017] [Accepted: 03/06/2017] [Indexed: 11/24/2022]
Abstract
Maternal effects, the influences of maternal phenotype on the phenotypes of her offspring, mediate early ontogenetic traits through maternal investment. In amphibians, provisioning eggs with yolk is the main source of maternal investment. While larger eggs generally result in larger, higher-quality offspring, the relationship between egg size and offspring phenotype is complicated because offspring can evolve to be more or less responsive to variation in yolk provisions. Previous studies of several ambystomatid salamanders suggest that the effects of embryonic yolk reserve reduction on hatchling life history traits increase with egg size. In this study, a similar controlled experimental yolk removal technique in Ambystoma mexicanum was used to determine the effects of reduced yolk reserves on phenotypes including hatching time and stage, hatchling and larval size and performance in predation trials with fish. Surprisingly, yolk reduction revealed no effects on any traits. These findings suggest that larval morphology in A. mexicanum is highly canalized and larval phenotypes are decoupled from yolk reserve variation. This surprising lack of yolk removal effects in hatchling and larval axolotls illustrates the evolutionary flexibility of early life history traits. Traits can evolve to increase or decrease their response to resources and can even become completely unresponsive. Since we found no effects in early life history, we hypothesize that domestication of the axolotl may have altered yolk properties or allocation dynamics and that maternal investment in yolk reserves may manifest at later life stages by reducing the time to reproductive maturity or increasing fecundity.
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39
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Wang Y, Zeng ZG, Ma L, Li SR, Du WG. Food restriction affects maternal investment but not neonate phenotypes in a viviparous lizard. Zool Res 2017; 38:81-87. [PMID: 28409503 PMCID: PMC5396030 DOI: 10.24272/j.issn.2095-8137.2017.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/03/2017] [Indexed: 01/08/2023] Open
Abstract
Food availability significantly affects an animal's energy metabolism, and thus its phenotype, survival, and reproduction. Maternal and offspring responses to food conditions are critical for understanding population dynamics and life-history evolution of a species. In this study, we conducted food manipulation experiments in field enclosures to identify the effect of food restriction on female reproductive traits and postpartum body condition, as well as on hatchling phenotypes, in a lacertid viviparous lizard from the Inner Mongolian desert steppe of China. Females under low-food availability treatment (LFT) had poorer immune function and body condition compared with those under high-food availability treatment (HFT). The food availability treatments significantly affected the litter size and litter mass of the females, but not their gestation period in captivity or brood success, or the body size, sprint speed, and sex ratio of the neonates. Females from the LFT group had smaller litter sizes and, therefore, lower litter mass than those from the HFT group. These results suggest that female racerunners facing food restriction lay fewer offspring with unchanged body size and locomotor performance, and incur a cost in the form of poor postpartum body condition and immune function. The flexibility of maternal responses to variable food availability represents an important life strategy that could enhance the resistance of lizards to unpredictable environmental change.
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Affiliation(s)
- Yang Wang
- Key Laboratory of Animal Ecology and Conservational Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi-Gao Zeng
- Key Laboratory of Animal Ecology and Conservational Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Liang Ma
- Key Laboratory of Animal Ecology and Conservational Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shu-Ran Li
- Key Laboratory of Animal Ecology and Conservational Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei-Guo Du
- Key Laboratory of Animal Ecology and Conservational Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
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40
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Zhang XY, Lou MF, Shen W, Fu RS, Wang DH. A Maternal Low-Fiber Diet Predisposes Offspring to Improved Metabolic Phenotypes in Adulthood in an Herbivorous Rodent. Physiol Biochem Zool 2017; 90:75-84. [DOI: 10.1086/688978] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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41
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Warner DA, Johnson MS, Nagy TR. Validation of Body Condition Indices and Quantitative Magnetic Resonance in Estimating Body Composition in a Small Lizard. ACTA ACUST UNITED AC 2016; 325:588-597. [PMID: 28035770 DOI: 10.1002/jez.2053] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/01/2016] [Accepted: 11/01/2016] [Indexed: 11/06/2022]
Abstract
Measurements of body condition are typically used to assess an individual's quality, health, or energetic state. Most indices of body condition are based on linear relationships between body length and mass. Although these indices are simple to obtain, nonlethal, and useful indications of energetic state, their accuracy at predicting constituents of body condition (e.g., fat and lean mass) are often unknown. The objectives of this research were to (1) validate the accuracy of another simple and noninvasive method, quantitative magnetic resonance (QMR), at estimating body composition in a small-bodied lizard, Anolis sagrei, and (2) evaluate the accuracy of two indices of body condition (based on length-mass relationships) at predicting body fat, lean, and water mass. Comparisons of results from QMR scans to those from chemical carcass analysis reveal that QMR measures body fat, lean, and water mass with excellent accuracy in male and female lizards. With minor calibration from regression equations, QMR will be a reliable method of estimating body composition of A. sagrei. Body condition indices were positively related to absolute estimates of each constituent of body composition, but these relationships showed considerable variation around regression lines. In addition, condition indices did not predict fat, lean, or water mass when adjusted for body mass. Thus, our results emphasize the need for caution when interpreting body condition based upon linear measurements of animals. Overall, QMR provides an alternative noninvasive method for accurately measuring fat, lean, and water mass in these small-bodied animals.
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Affiliation(s)
- Daniel A Warner
- Department of Biology, University of Alabama at Birmingham, Birmingham, Alabama.,Department of Biological Sciences, Auburn University, Auburn, Alabama
| | - Maria S Johnson
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama
| | - Tim R Nagy
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama
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42
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Does Reduced Perch Availability Affect Reproduction in the Brown Anole? An Experimental Test in the Laboratory. J HERPETOL 2016. [DOI: 10.1670/14-147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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43
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Sockman KW. The Regulation of Behavioral Plasticity by Performance-Based Feedback and an Experimental Test with Avian Egg Production. Am Nat 2016; 187:564-75. [PMID: 27104990 DOI: 10.1086/685881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Optimizing plasticity in behavioral performances requires the abilities to regulate physiological effort and to estimate the effects of the environment. To describe how performance-based feedback could play a role in regulating recursive or continuous behavioral performances, I developed two models, one (environmental feedback) that assumes an initial ability to regulate effort but not to predict the effects of the environment and the other (effort feedback) that assumes an initial ability to predict the effects of the environment but not to regulate effort. I tested them by manipulating feedback on egg production, using an egg-substitution experiment in wild, free-ranging Lincoln's sparrows (Melospiza lincolnii). I discovered that females adjusted the size of their clutches' third laid eggs in response to the size of an experimentally substituted first laid egg, such that the size of the third laid egg increased with the size of the substitute. Results were largely consistent with the environmental feedback model, though small portions of the response surface were consistent with the effort feedback model or with neither. Regardless, such feedback-based regulation predicted by either model may help females maximize net benefits of egg production and may be a basis for mechanisms regulating a wide range of other behavioral performances, as well.
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44
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Bonduriansky R, Runagall‐McNaull A, Crean AJ. The nutritional geometry of parental effects: maternal and paternal macronutrient consumption and offspring phenotype in a neriid fly. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12643] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Russell Bonduriansky
- Evolution & Ecology Research Centre School of Biological, Earth and Environmental Sciences UNSW Australia Sydney NSW 2052 Australia
| | - Aidan Runagall‐McNaull
- Evolution & Ecology Research Centre School of Biological, Earth and Environmental Sciences UNSW Australia Sydney NSW 2052 Australia
| | - Angela J. Crean
- Evolution & Ecology Research Centre School of Biological, Earth and Environmental Sciences UNSW Australia Sydney NSW 2052 Australia
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45
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Eizadshenass S, Singh RS. Maternal effect and speciation: maternal effect contributes to the evolution of hybrid inviability between Drosophila simulans and Drosophila mauritiana. Genome 2015; 58:405-13. [PMID: 26436586 DOI: 10.1139/gen-2015-0053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Haldane's rule has been the basis of speciation research during the last 30 years. Most studies have focused on the nature of incompatibilities in the hybrid male, but not much attention has been given to the genetic basis of fertility and inviability in hybrid females. Hybridizations between Drosophila simulans and Drosophila mauritiana produce fertile females and sterile males. Here, we re-examined the level of fertility in reciprocal F1 females of these two species and looked for the presence of maternal effects. Our results show that the reciprocal F1 females of D. simulans and D. mauritiana hybridizations are fully fertile and in fact show a significant level of heterosis in the rate of oviposition but display reduced egg hatching in one direction. Reduced egg hatching was observed in the progenies of F1 hybrid females with D. mauritiana as mother, the same cross that showed a stronger negative effect on F1 male fertility. A review of the literature on the hybridizations in Lepidoptera also showed a maternal effect on inviability when reciprocal crosses produced asymmetric results. Our findings point to the importance of maternal effects in the evolution of embryo inviability and thus enhancing the process of speciation through the evolution of hybrid inviability.
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Affiliation(s)
- Sogol Eizadshenass
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada.,Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada
| | - Rama S Singh
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada.,Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada
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46
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Calsbeek R, Duryea MC, Goedert D, Bergeron P, Cox RM. Intralocus sexual conflict, adaptive sex allocation, and the heritability of fitness. J Evol Biol 2015; 28:1975-85. [PMID: 26310599 DOI: 10.1111/jeb.12713] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 06/25/2015] [Accepted: 07/29/2015] [Indexed: 11/27/2022]
Abstract
Intralocus sexual conflict arises when selection favours alternative fitness optima in males and females. Unresolved conflict can create negative between-sex genetic correlations for fitness, such that high-fitness parents produce high-fitness progeny of their same sex, but low-fitness progeny of the opposite sex. This cost of sexual conflict could be mitigated if high-fitness parents bias sex allocation to produce more offspring of their same sex. Previous studies of the brown anole lizard (Anolis sagrei) show that viability selection on body size is sexually antagonistic, favouring large males and smaller females. However, sexual conflict over body size may be partially mitigated by adaptive sex allocation: large males sire more sons than daughters, whereas small males sire more daughters than sons. We explored the evolutionary implications of these phenomena by assessing the additive genetic (co)variance of fitness within and between sexes in a wild population. We measured two components of fitness: viability of adults over the breeding season, and the number of their progeny that survived to sexual maturity, which includes components of parental reproductive success and offspring viability (RS(V) ). Viability of parents was not correlated with adult viability of their sons or daughters. RS(V) was positively correlated between sires and their offspring, but not between dams and their offspring. Neither component of fitness was significantly heritable, and neither exhibited negative between-sex genetic correlations that would indicate unresolved sexual conflict. Rather, our results are more consistent with predictions regarding adaptive sex allocation in that, as the number of sons produced by a sire increased, the adult viability of his male progeny increased.
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Affiliation(s)
- R Calsbeek
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - M C Duryea
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - D Goedert
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA.,CAPES Foundation, Ministry of Education of Brazil, Brasília, DF, Brazil
| | - P Bergeron
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - R M Cox
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
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47
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Warner DA, Buckelew AM, Pearson PR, Dhawan A. The effect of prey availability on offspring survival depends on maternal food resources. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12519] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel A. Warner
- Department of Biology; University of Alabama at Birmingham; Birmingham AL 35209 USA
| | - Andrew M. Buckelew
- Department of Biology; University of Alabama at Birmingham; Birmingham AL 35209 USA
| | - Phillip R. Pearson
- Department of Biology; University of Alabama at Birmingham; Birmingham AL 35209 USA
| | - Agam Dhawan
- Department of Biology; University of Alabama at Birmingham; Birmingham AL 35209 USA
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48
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Warner DA. Fitness Consequences of Maternal and Embryonic Responses to Environmental Variation: Using Reptiles as Models for Studies of Developmental Plasticity. Integr Comp Biol 2014; 54:757-73. [DOI: 10.1093/icb/icu099] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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